EP0374744A2 - Microwave integrated circuit - Google Patents

Microwave integrated circuit Download PDF

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Publication number
EP0374744A2
EP0374744A2 EP89123197A EP89123197A EP0374744A2 EP 0374744 A2 EP0374744 A2 EP 0374744A2 EP 89123197 A EP89123197 A EP 89123197A EP 89123197 A EP89123197 A EP 89123197A EP 0374744 A2 EP0374744 A2 EP 0374744A2
Authority
EP
European Patent Office
Prior art keywords
integrated circuit
microwave integrated
variable capacitance
circuit
circuit according
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP89123197A
Other languages
German (de)
French (fr)
Other versions
EP0374744B1 (en
EP0374744A3 (en
Inventor
Nobuo C/O Yokohama Works Of Sumitomo Shiga
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Sumitomo Electric Industries Ltd
Original Assignee
Sumitomo Electric Industries Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Sumitomo Electric Industries Ltd filed Critical Sumitomo Electric Industries Ltd
Publication of EP0374744A2 publication Critical patent/EP0374744A2/en
Publication of EP0374744A3 publication Critical patent/EP0374744A3/en
Application granted granted Critical
Publication of EP0374744B1 publication Critical patent/EP0374744B1/en
Anticipated expiration legal-status Critical
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Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L27/00—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate
    • H01L27/02—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having at least one potential-jump barrier or surface barrier; including integrated passive circuit elements with at least one potential-jump barrier or surface barrier
    • H01L27/04—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having at least one potential-jump barrier or surface barrier; including integrated passive circuit elements with at least one potential-jump barrier or surface barrier the substrate being a semiconductor body
    • H01L27/06—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having at least one potential-jump barrier or surface barrier; including integrated passive circuit elements with at least one potential-jump barrier or surface barrier the substrate being a semiconductor body including a plurality of individual components in a non-repetitive configuration
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H7/00—Multiple-port networks comprising only passive electrical elements as network components
    • H03H7/38—Impedance-matching networks
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
    • H01P5/00—Coupling devices of the waveguide type
    • H01P5/08—Coupling devices of the waveguide type for linking dissimilar lines or devices
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F3/00—Amplifiers with only discharge tubes or only semiconductor devices as amplifying elements
    • H03F3/60—Amplifiers in which coupling networks have distributed constants, e.g. with waveguide resonators
    • H03F3/601—Amplifiers in which coupling networks have distributed constants, e.g. with waveguide resonators using FET's, e.g. GaAs FET's
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H11/00—Networks using active elements
    • H03H11/02—Multiple-port networks
    • H03H11/28—Impedance matching networks

Definitions

  • MMIC monolithic MIC
  • a field effect transistor such as a GaAs FET.
  • Fig. 1 A general circuit configuration of the MMIC is shown in which a source of a FET 21 is grounded, an input matching circuit 22 is connected to an input terminal of MMIC and an output matching circuit 23 is connected to an output terminal of MMIC.
  • Constants of elements in the input matching circuit 22 are set in accordance with the characteristic.
  • the matching characteristic of the initial stage amplifier has been designed by taking primary consideration of only one of the noise matching characteristic and the gain matching characteristic, depending on the application.
  • the circuit designed primarily for the noise matching characteristic can provide a minimum noise figure (hereinafter NF) but a gain of the initial stage amplifier is low and an input voltage standing wave ratio (hereinafter VSWR) is high.
  • the gain of the initial stage is high and the input VSWR is low, but the NF is high.
  • a microwave integrated circuit having a plurality of circuit components integrated therein, comprises an initial stage amplification means having a field effect transistor and a series circuit means having an inductive element and a variable capacitance element which are serially connected to each other and one end of the series circuit means is connected to a source of the field effect transistor and the other end being connected to ground.
  • Fig. 2 shows one embodiment of an initial amplification circuit of MMIC of the present invention.
  • a field effect transistor 5 such as GaAs MESFET or HEMT has a gate thereof connected to the microstrip 3.
  • An inductor 6 is constructed by a microstrip having one end thereof connected to a source of the FET 5.
  • a variable capacitance diode 7 has an anode thereof connected to one end of the inductor 6 and a cathode thereof grounded and a microstrip 8 has one end thereof connected to a junction of the inductor 6 and the variable capacitance diode 7.
  • a resistor 9 has one end thereof connected to the other end of the microstrip 8, and an external terminal 10 is connected to the other end of the resistor 9.
  • the imaginary part of the signal source impedance Z opt changes in accordance with the combined impedance L s .
  • Z opt changes as shown by the arrow on the Smith chart. Namely, it changes along a constant resistance circle in a direction to reduce the reactance.
  • the present invention is also applicable to a hybrid MIC and a discrete component circuit with a similar advantage.

Abstract

In a microwave integrated circuit, a series circuit of an inductive element (6) and a variable capacitance element (7) is inserted between a source of a field effect transistor (5) of an initial stage circuit and ground. The capacitance of the variable capacitance element (7) is controlled by an input signal applied to an external terminal (10) so that an input impedance of the initial stage circuit is properly changed by the input signal applied to the external terminal (10). Thus, it is possible to set a system to an input matching characteristic which has both a noise matching characteristic and a gain matching characteristic which fit to a system specification.

Description

    Background of the Invention (Field of the Invention)
  • The present invention relates to a low noise amplification microwave integrated circuit (hereinafter MIC) for use in a satellite broadcasting receiving converter or microwave communication, and more particularly to an improvement in an input matching characteristic thereof.
    • (Related Background Art)
  • One of prior art low noise amplification MICs uses a monolithic MIC (hereinafter MMIC) which uses a field effect transistor such as a GaAs FET. A general circuit configuration of the MMIC is shown in Fig. 1 in which a source of a FET 21 is grounded, an input matching circuit 22 is connected to an input terminal of MMIC and an output matching circuit 23 is connected to an output terminal of MMIC.
  • In an input matching characteristic of an initial stage amplifier in a multi-stage amplification MMIC circuit, either a noise matching characteristic which requires a low noise characteristic is important or a gain matching characteristic which requires a high gain characteristic is important, depending on an application of the circuit. Constants of elements in the input matching circuit 22 are set in accordance with the characteristic.
  • In the prior art MMIC, the matching characteristic of the initial stage amplifier has been designed by taking primary consideration of only one of the noise matching characteristic and the gain matching characteristic, depending on the application. The circuit designed primarily for the noise matching characteristic can provide a minimum noise figure (hereinafter NF) but a gain of the initial stage amplifier is low and an input voltage standing wave ratio (hereinafter VSWR) is high.
  • In the circuit designed primarily for the gain matching characteristic, the gain of the initial stage is high and the input VSWR is low, but the NF is high.
    • Summary of the Invention
  • The present invention intends to solve those problems. In the present invention, a microwave integrated circuit having a plurality of circuit components integrated therein, comprises an initial stage amplification means having a field effect transistor and a series circuit means having an inductive element and a variable capacitance element which are serially connected to each other and one end of the series circuit means is connected to a source of the field effect transistor and the other end being connected to ground.
  • The present invention will become more fully under­stood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus are not to be considered as limiting the present invention.
  • Further scope of applicability of the present inven­tion will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
    • Brief Description of the Drawings
    • Fig. 1 is a block diagram of a prior art circuit configuration,
    • Fig. 2 is a block diagram of one embodiment of the present invention, and
    • Fig. 3 is a Smith chart for a signal source impedance Zopt and an input reflection coefficient S₁₁* in the embodiment.
    Description of the preferred Embodiments
  • The present invention is now explained in detail with reference to the drawings.
  • Fig. 2 shows one embodiment of an initial amplification circuit of MMIC of the present invention.
  • As shown in Fig. 2, a microwave signal is applied through a signal input terminal 1 to the initial stage amplification circuit, a capacitor 2 blocks a DC component of an input signal, a microstrip 3 is connected in series to the capacitor 2. An another microstrip 4 has one end thereof connected to a junction of the capacitor 2 and the microstrip 3. The microstrips 3 and 4 form an input matching circuit.
  • A field effect transistor 5 (hereinafter FET) such as GaAs MESFET or HEMT has a gate thereof connected to the microstrip 3. An inductor 6 is constructed by a microstrip having one end thereof connected to a source of the FET 5. A variable capacitance diode 7 has an anode thereof connected to one end of the inductor 6 and a cathode thereof grounded and a microstrip 8 has one end thereof connected to a junction of the inductor 6 and the variable capacitance diode 7. A resistor 9 has one end thereof connected to the other end of the microstrip 8, and an external terminal 10 is connected to the other end of the resistor 9.
  • Microstrips 11 and 12 are connected in series to a drain of the FET 5, and a microstrip 13 has one end thereof connected to a junction of the microstrip 11 and 12 and the other end thereof grounded. Those microstrips 11, 12 and 13 constitute an interstage matching circuit in the multi-stage circuit. A DC blocking capacitor 14 is connected to the microstrip 12, and an output terminal 15 is connected to a succeeding stage circuit.
  • In the present circuit, a combined impedance Z is given by
    Z = jωL + 1/jωC
    = jω (L - 1/ω²C)      (1)
    where L is an inductance of the inductor 6, and C is a capacitance of the variable capacitance diode 7.
  • The constants are selected such that
    L > 1/ω²C
    is met, where ω is an operating frequency band, and the capacitance C of the variable capacitance diode 7 is changed in accordance with the signal applied to the external terminal 10 so that the combined impedance Z is changed as a combined inductance Ls.
  • By changing the combined impedance Z, that is, by changing the combined inductance Ls of the inductance 6 and the variable capacitance diode 7, Zopt (a signal source impedance which causes a minimum NF) and S₁₁* (a complex conjugate number of the input reflection coefficient) are controlled such that Zopt and S₁₁* change on the Smith chart shown in Fig. 3 in a manner shown by arrows. The reason therefore is explained below.
  • The input impedance Zin of the FET 5(which corresponds to S₁₁ in the Smith chart) is given by:
    Zin = RG+Rin+Rs+Gm·L­s/Cgs+1/(j·ω·Cgs)      (2)
    where RG: gate resistance of the FET 5
    Rin:channel resistance
    Rs: source resistance
    Cgs: gate-source capacitance
    Gm: transfer conductance
    Zopt is represented by:
    Zopt = Ropt + j (Xopt - ω/Ls)      (3)
    where Ropt* real part of the signal source impedance which causes a minimum NF by the FET 5 alone.
    Xopt: imaginary part thereof
    As seen from the formula (2), the real part of the input impedance Zin changes in accordance with the combined impedance Ls. As the combined impedance Ls is increased by the signal applied to the external terminal 10, the complex conjugate number S₁₁* of S₁₁ changes as shown by the arrow on the Smith chart of Fig. 3. Namely, it changes along a constant reactance line in a direction to increase the resistance.
  • The imaginary part of the signal source impedance Zopt changes in accordance with the combined impedance Ls. As the combined impedance Ls increases, Zopt changes as shown by the arrow on the Smith chart. Namely, it changes along a constant resistance circle in a direction to reduce the reactance.
  • Accordingly, by properly selecting the combined impedance Ls(Z) by the input signal applied to the external 10, S₁₁* and Zopt approach to each other on the Smith chart so that the trade-off between the noise matching characteristic and the gain matching characteristic is optimized.
  • While the initial stage amplification circuit of the MMIC has been described in the present embodiment, the present invention is applicable to a multi-stage amplification type MMIC in which a plurality of the initial stage amplification circuits are connected in series.
  • While the MMIC has been described in the present embodiment, the present invention is also applicable to a hybrid MIC and a discrete component circuit with a similar advantage.
  • From the invention thus described, it will be obvious that the invention may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.

Claims (7)

1. A microwave integrated circuit having a plurality of circuit components integrated therein, comprising:
- an initial stage amplification means having a field effect transistor (5); and
- a series circuit means (6,7) having an inductive element (6) and a variable capacitance element (7) which are connected in series to each other,
one end of said series circuit means (6,7) being connected to a source of said field effect transistor (5) and the other end being connected to ground.
2. A microwave integrated circuit according to claim 1, further comprising control means (8,9) for controlling the capacitance of said variable capacitance element (7) by an external input signal.
3. A microwave integrated circuit according to claim 2, wherein said control means (8,9) for controlling comprises a circuit of a microstrip (8) and a resistor (9) which are serially connected to each other one end thereof being connected to a junction of said variable capacitance element (7) and said inductive element (6) and the other end thereof being connected to an external terminal (10) thereof.
4. A microwave integrated circuit according to claim 1, 2, or 3, wherein a gate of said field effect transistor (5) is electrically connected to an input terminal (1) of said microwave integrated circuit.
5. A microwave integrated circuit according to any preceding claim, wherein said variable capacitance element comprises a variable capacitance diode (7).
6. A microwave integrated circuit according to any preceding claim, wherein said inductive element comprises a microstrip (6).
7. A method of controlling a microwave integrated circuit according to any preceding claim, characterized by changing the capacitance of said variable capacitance element (7) in a range which meets
L > 1/ω²C
where L is an inductance of said inductive element and ω is an operating frequency band.
EP89123197A 1988-12-22 1989-12-15 Microwave integrated circuit Expired - Lifetime EP0374744B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP63324357A JPH02170602A (en) 1988-12-22 1988-12-22 Microwave integrated circuit
JP324357/88 1988-12-22

Publications (3)

Publication Number Publication Date
EP0374744A2 true EP0374744A2 (en) 1990-06-27
EP0374744A3 EP0374744A3 (en) 1991-05-29
EP0374744B1 EP0374744B1 (en) 1995-05-10

Family

ID=18164882

Family Applications (1)

Application Number Title Priority Date Filing Date
EP89123197A Expired - Lifetime EP0374744B1 (en) 1988-12-22 1989-12-15 Microwave integrated circuit

Country Status (6)

Country Link
US (1) US5010305A (en)
EP (1) EP0374744B1 (en)
JP (1) JPH02170602A (en)
KR (1) KR930011384B1 (en)
CA (1) CA2005182A1 (en)
DE (1) DE68922594T2 (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0637131A1 (en) * 1993-07-29 1995-02-01 Nec Corporation Microwave amplifier having a variable-impedance impedance matching circuit
EP0833442A1 (en) * 1996-09-27 1998-04-01 Nortel Networks Corporation High frequency noise and impedance matched integrated circuits
EP1998439A1 (en) * 2006-03-20 2008-12-03 Fujitsu Limited Analog circuit

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH03296311A (en) * 1990-04-13 1991-12-27 Sumitomo Electric Ind Ltd Low noise amplifier
JPH0575357A (en) * 1991-09-10 1993-03-26 Mitsubishi Electric Corp Low noise amplifier
US5602501A (en) * 1992-09-03 1997-02-11 Sumitomo Electric Industries, Ltd. Mixer circuit using a dual gate field effect transistor
US5410745A (en) * 1993-05-20 1995-04-25 Motorola, Inc. Detector and video amplifier
US6121840A (en) * 1996-12-24 2000-09-19 Murata Manufacturing Co., Ltd. High-frequency amplifier
JP4220694B2 (en) * 2001-03-27 2009-02-04 パナソニック株式会社 High frequency variable gain amplifier
US8803599B2 (en) * 2010-05-26 2014-08-12 Stmicroelectronics, Inc. Dendrite resistant input bias network for metal oxide semiconductor field effect transistor (MOSFET) devices
KR101503146B1 (en) 2013-08-05 2015-03-16 삼성전기주식회사 Low Noise Amplifier

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3327107A1 (en) * 1982-07-28 1984-02-09 Fujitsu Ten Ltd., Kobe, Hyogo Radio-frequency amplifier circuit
US4658220A (en) * 1985-09-06 1987-04-14 Texas Instruments Incorporated Dual-gate, field-effect transistor low noise amplifier

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4670722A (en) * 1981-03-09 1987-06-02 The United States Of America As Represented By The Secretary Of The Navy FET oscillator having controllable reactance element-controlled two port feedback network
US4458215A (en) * 1981-08-17 1984-07-03 Rca Corporation Monolithic voltage controlled oscillator
US4683443A (en) * 1986-01-27 1987-07-28 The United States Of America As Represented By The Secretary Of The Air Force Monolithic low noise amplifier with limiting

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3327107A1 (en) * 1982-07-28 1984-02-09 Fujitsu Ten Ltd., Kobe, Hyogo Radio-frequency amplifier circuit
US4658220A (en) * 1985-09-06 1987-04-14 Texas Instruments Incorporated Dual-gate, field-effect transistor low noise amplifier

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
H. Tholl: Bauelemente der Halbleiterelektronik, pages 84 - 89, Teubner, Stuttgart, DE, 1976 *
IEEE TRANSACTIONS ON ELECTRON DEVICES. vol. ed.32, no. 12, December 1985, NEW YORK US pages 2729 - 2735; R. E. Lehmann et al.: "X-Band Monolithic Series Feedback LNA" *

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0637131A1 (en) * 1993-07-29 1995-02-01 Nec Corporation Microwave amplifier having a variable-impedance impedance matching circuit
EP0833442A1 (en) * 1996-09-27 1998-04-01 Nortel Networks Corporation High frequency noise and impedance matched integrated circuits
EP1998439A1 (en) * 2006-03-20 2008-12-03 Fujitsu Limited Analog circuit
EP1998439A4 (en) * 2006-03-20 2009-04-15 Fujitsu Ltd Analog circuit
EP2166667A2 (en) * 2006-03-20 2010-03-24 Fujitsu Limited Analog circuit
EP2166667A3 (en) * 2006-03-20 2010-05-05 Fujitsu Limited Analog circuit
US7782140B2 (en) 2006-03-20 2010-08-24 Fujitsu Limited Analog circuit
EP2296268A1 (en) * 2006-03-20 2011-03-16 Fujitsu Limited Analog circuit

Also Published As

Publication number Publication date
DE68922594D1 (en) 1995-06-14
KR910013544A (en) 1991-08-08
CA2005182A1 (en) 1990-06-22
EP0374744B1 (en) 1995-05-10
DE68922594T2 (en) 1996-02-01
JPH02170602A (en) 1990-07-02
EP0374744A3 (en) 1991-05-29
KR930011384B1 (en) 1993-12-04
US5010305A (en) 1991-04-23

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